1. Field of the Invention
The present invention relates to a fastener for packaging which is particularly suitable for a packaging box which is made of cardboard or the like for packaging a product of a large weight.
2. Description of the Related Art
As a box for packaging the product of a large weight, there has been a box which can be divided into an upper box and a lower box for facilitating packaging as well as opening and closing of the box. Various kinds of fasteners for packaging which can connect these divided packaging boxes have been proposed in the past and one of such fasteners for packaging is disclosed in Japanese Patent Publication No. Hei 1-16743/1989.
In the structure of the fastener for packaging disclosed in the above-mentioned publication, the fastener for packaging is comprised of two members, that is, a cylindrical base body having a hook portion and a key body which is pushed into the inside of the base body so as to forcibly expand the hook portion. On the other hand, through holes are formed in portions of the upper and lower boxes to be connected which are overlapped with each other. In connecting the upper and lower boxes, an upper plate and a lower plate are overlapped with each other while aligning the positions of the through holes, and the base body of the fastener for packaging is inserted into the through holes, and subsequently, the key body of the fastener for packaging is inserted and pushed into the base body so as to forcibly expand the hook portion thus fixedly securing the fastener for packaging to the upper and lower boxes and accordingly connecting the upper and lower boxes with such a securing.
As described above, in the conventional fastener for packaging disclosed in the Japanese Patent Publication No. Hei 1-16743/1989, it is necessary to push the key body into the base body after inserting the base body into the through holes and hence, it is necessary to perform two manipulations. Accordingly, the operation is cumbersome. Further, the key body is pushed into the base body and is held in that state by such a pushing and so that the key body becomes relatively large. Accordingly, with the holding structure which simply pushes the key body into the base body, the key is liable to be easily removed by a local external force.
The present invention has been made under the above-mentioned background and it is an object of the present invention to provide a fastener for packaging which can solve the above-mentioned problems thoroughly, has a relatively simple structure, and can perform the connecting operation easily thus having a favorable usability. Further objects of the present invention become apparent in the description which is explained hereinafter in sequence.
To achieve the above-mentioned object, the present invention is directed to a fastener for packaging which connects a first plate body and a second plate body respectively having through holes in a state that the first plate body and the second plate body are overlapped in an up and down direction or a left and right direction with the through holes being aligned with each other and comprises a base body formed with a thickness which corresponds to the through holes and being insertable into respective through holes, a first flange portion and a second flange portion which extend in the approximately horizontal direction from one portions of upper and lower sides of an outer surface of the base body, the first flange portion and the second flange portions clamping the first and second plate bodies from front and rear surfaces in a state that the base body is completely inserted into both through holes, a movable hook member having an approximately L shape, the movable hook member rotatably connected to a portion of the base body in the vicinity of a lower end edge out of lower end edges of the base body which is disposed apart from the second flange portion by way of a hinge portion, the movable hook member being rotated from a through hole insertion initial position where a horizontal portion of the L shape is moved away from a corresponding side surface of the base body and is directed downwardly to a through hole mounting position where a vertical portion of the L shape is brought into contact with the corresponding side surface of the base body and the horizontal portion of the L shape is brought into contact with the rear surface of the second plate body as a third flange portion in the same manner as the second flange portion, and lock means provided to corresponding side surfaces of the movable hook member and the base body, the lock means capable of holding and locking a state which the movable hook member takes when the movable hook member is rotated to the through hole mounting position by way of the hinge portion.
Here, the first flange portion is mounted on the upper side of the outer surface of the base body. This mounting of the first flange portion on the upper side of the outer surface includes a mode in which the flange portion is formed by contiguously protruding from a portion of the upper side of the outer surface other than a portion which corresponds to the movable hook member and a mode in which flange portions are protruded from a plurality of portions of the upper side of the outer surface in a non-contiguous manner. On the other hand, the second flange portion is mounted on a portion of the lower side of the outer surface of the base body. In this case, it is important that the second flange portion is mounted apart from the movable hook member. Accordingly, the mounting of the second flange portion on the lower side of the outer surface of the base body is not limited to a mode in which the second flange portion is formed by protruding from a portion which faces the movable hook member in an opposed manner shown in FIG. 2. For example, by forming the through holes which allow protruding portions indicated by symbols X in FIG. 2 to pass therethrough in the first plate body and the second plate body, a mode in which the second flange portions are formed in a protruding manner at portions indicated by symbols X in FIG. 2, that is, portions which are positioned at both sides of the base body and apart from the movable hook members or a mode in which the second flange portions are in a protruding manner formed at the above-mentioned portions contiguously or non-contiguously may be adopted.
Due to the above-mentioned constitution, as illustrated in FIG. 9, with respect to both through holes of the first and second plate bodies, with the movable hook member held in a state of the initial position of the through hole insertion by way of the hinge portion where the horizontal portion of the L shape is directed downwardly and the vertical portion is directed approximately horizontally, when the base body has the lower-side second flange portion thereof passed through both through holes of the first and second plate bodies and moved to the rear surface side of the second plate body, the (downwardly directed) horizontal portion of the L-shape falls into the inside of the holes until the movement of the (approximately horizontally directed) vertical portion is restricted by being brought into contact with the surface side of the first plate body. Simultaneously, a portion of the first flange portion and the second flange portion sandwich the total thickness of the first and second plate bodies from front and back. From this state, for example, when the base body is pushed or pressed from an upper side which corresponds to the hinge portion, while the base body is pushed into both through holes shown in FIG. 10, due to a downward stress, the (approximately horizontally directed) vertical portion of the L-shape is rotated in the direction to come into contact with the corresponding side surface of the base body about the receiving hinge portion as a fulcrum and takes a normal vertical position and simultaneously the horizontal portion of the L-shape is rotatably moved from the downwardly directed state to the rear surface side of the second plate body, that is, to the horizontal state. Accordingly, the fastener of the present invention is bound to the first and second plate bodies which are overlapped with a given clamping force in the state that the first flange portion of the base body is positioned at the front surface side and the second flange portion and the horizontal portion of the L-shape which works as the third flange portion are positioned at the rear surface side. Further, this binding state is surely locked and held by the lock means provided between the base body and the movable hook member.